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Chinese ship hears pulse signal in south Indian Ocean

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posted on Apr, 5 2014 @ 12:03 PM
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reply to post by tanka418
 


It doesn't matter that the ocean depth is around 5000 metres in the search area, an ELT transmitting at 406 MHz doesn't have even close to that range in water. A higher frequency is even worse.

This is why they install UABs on the FDRs and CVRs. The 37.5 kHz signal from a UAB has a range of around 2 km in normal conditions, depending on the transmitter signal strength.

This is much greater than an ELT. ELTs are really only useful for crashes on land.




posted on Apr, 5 2014 @ 12:05 PM
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roadgravel

It was on, it was answering connections from the ground station via the satellite. How could it been off all flight.


I dunno what you are talking about, who said it was off all flight?

The ping from the secondary system is what I am talking about, the main ACARS system was off, and it was the secondary system that was saying "Hello" every hour but that's all.



posted on Apr, 5 2014 @ 12:32 PM
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erwalker
reply to post by tanka418
 


It doesn't matter that the ocean depth is around 5000 metres in the search area, an ELT transmitting at 406 MHz doesn't have even close to that range in water. A higher frequency is even worse.

This is why they install UABs on the FDRs and CVRs. The 37.5 kHz signal from a UAB has a range of around 2 km in normal conditions, depending on the transmitter signal strength.

This is much greater than an ELT. ELTs are really only useful for crashes on land.



You got an authority on this? some kind of reference? Its been a few decades, but, as I remember, radio does in fact penetrate water, though not well.

However, the system would have plenty of time to connect with a satellite before sinking...given that these systems activate on impact...A modern system would have relayed GPS data of the crash site.

Further, the ocean depth is critically important to finding anything contained...even the acoustic beacon would have difficulty with 5000 meters of water. AND, there is yet another issue; in that, necessary equipment had to be sent to the region(?) Really? to detect a signal that virtually ship sonar should be able to detect?

No...sorry man...more lies, or "wishful thinking"...



posted on Apr, 5 2014 @ 01:12 PM
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I'm sorry guys, you all kind of lost me with the technical aspects of the receivers/transponders.
That's where my knowledge ends. . .

Can someone fill me in(in lehman's terms) with what your all debating about, if not I just hang out for now until I figure it out!

Thanx, AB
edit on 4/5/2014 by AnteBellum because: spelling



posted on Apr, 5 2014 @ 01:21 PM
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There was the audit that found the improper storage MAS batteries in conditions that reduced their life span considerably. Who knows if any of the signals lasted long.



posted on Apr, 5 2014 @ 02:12 PM
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Let this be an example, maybe not great, but an example of all countries working together in time of crisis

just like the current ebola story
a global community needs global stories

...someone wake me up if/when the plane gets found?



posted on Apr, 5 2014 @ 02:58 PM
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AnteBellum
reply to post by AnteBellum
 


The alleged signal is from location -25D 0' 0", +101D 0' 0".

Something that bothers me about this is that there still is no debris.
I mean not one thing. . . luggage, lifeboats, purses, seat covers, etc!

I can only assume that if this is the location, that the jet pulled off a 'Sullenberger' type landing. But even then, wouldn't air pressure crush the jet spilling it contents as it went down to the depths?

I don't get it yet. . .

edit on 4/5/2014 by AnteBellum because: add


The doors are designed to resist positive air pressure - a higher air pressure inside the passenger compartment than outside. But once the plane is on water, air will slowly leak out and water will leak in. So long as the plane remains intact it would float for a while. That's been designed to allow passengers to evacuate onto life rafts.

Once the plane is partially submerged under water, air would be forced out and the plane will sink slowly.

The aerodynamical, airframe and flight control system is designed to prevent a stall and nosedive.
edit on 5-4-2014 by stormcell because: (no reason given)



posted on Apr, 5 2014 @ 03:23 PM
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I don't know if this has been covered yet. I was watching Fox News a bit ago, they were discussing this newly announced, by the Chinese government new *ping*.

Apparently, it was supposedly picked up by one person, via headphones, with no recording device to verify it, nor any GPS coordinates to link the ping with.

It all sounds extremely dubious to me. With all the misinformation being tossed out on the the missing plane, by so many varying factions, I find it hard to take it as seriously as some are. But, that's just me.

Des



edit on 5-4-2014 by Destinyone because: (no reason given)



posted on Apr, 5 2014 @ 04:12 PM
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reply to post by tanka418
 


You could check out the following article, originally published in Amateur Radio, April 1987.

Underwater Communication

You will find note that the distance travelled by RF in water is inversely proportional to the frequency. A one watt 1.8 Mhz signal travels approx. 28 meter underwater. A receiver 30 metres away would be very unlikely to pick it up. Increase the transmitter power by 100 watts and you get range increase of approx. 3.7 metres. That's metres and not kilometres. The range is even less if the receiver is located above the water because the passing of the RF from water to air further weakens the signal. An ELT transmits at 406 Mhz, which would reduce the range even further.

There is no guarantee that the ELT would have be above water long enough for anything to pick up a transmission in the event of a crash in the ocean and most of them do not float. There is no requirement for that in the regulations currently in effect governing civil aviation. A plane like the military P-3 Orion on the other hand has a fibreglass and foam airfoil with the FDR, CVR, and ELT embedded in it, which will deploy on command or automatically in the event of a crash. That airfoil floats and its ELT signal would be able to be picked up.

As I said previously, a UAB has a much further range do to it transmitting on a very low frequency. While a human can't hear the signal without using some sort of electronic receiver, that 37.5 kHz signal is within the range of the hearing of such animals as dogs and cats. Not that that is of any use in this case. See UAB for more, including the range.



posted on Apr, 5 2014 @ 05:34 PM
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reply to post by stormcell
 


You answered one of my question then - totally different then what I was thinking.
My assumption was when that last bit of air rushed out, once the jet was already submerged and sinking, the pressure difference would blow the doors, panels or windows, off and out(some not all).
I wonder if there are any videos showing testing of this?
Has anyone taken a spent jet and sank it into the ocean to see?
I going to go look around when I get a chance.

Thanks, AB
edit on 4/5/2014 by AnteBellum because: add



posted on Apr, 5 2014 @ 08:02 PM
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tanka418

You got an authority on this? some kind of reference?


Why, yes, yes I do:



The Man says that attenuation of a signal in a medium is related to the frequency of the signal and the conductivity, permittivity and permittivity of the medium it's propagating through.

In particular, for water the thing reduces to 0.0173 x sqrt(fC) where f is the frequency of the signal and C is the conductivity in Siemens per meter. Seawater is an average of 4 S/m. So, for a 400MHz signal, you get 0.0173 x sqrt(400,000,000 x 4) or about 692 db/meter loss. That's a lot.

It's also why the Navy sends signals to submarines with frequencies in the 20kHz range. The losses are still horrific but not as bad as that.



AND, there is yet another issue; in that, necessary equipment had to be sent to the region(?) Really? to detect a signal that virtually ship sonar should be able to detect?

No...sorry man...more lies, or "wishful thinking"...


You wouldn't use a ship's sonar to detect that sort of thing. A hydrophone system could, so any decent military ship would have gear that should be able to, our subs could do it easily. But you're not going to get them to do that, because it sort of gives away what and how well they can do. Not only that, since the signal isn't going to be very strong, you might do better with purpose-built designs.




posted on Apr, 5 2014 @ 09:49 PM
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I will just make that bold statement: they wont find anything



posted on Apr, 5 2014 @ 09:50 PM
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reply to post by aLLeKs
 





I will just make that bold statement: they wont find anything


of course not the search is being carried out now for more political reasons than anything else.



posted on Apr, 5 2014 @ 10:01 PM
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If it ends up being the actual black box . . .

Maybe the Chinese found it so quickly because they just dumped it over the side of their ship.



posted on Apr, 6 2014 @ 12:40 AM
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FlyersFan
I'd like to know why it took them a whole month to get ships in there to start the pinging?? Why didn't Malaysia bring in subs and ships from China to begin with? (they are close by and they had a ton of people on that plane) This whole thing has been messed up.

I hope they find the wreckage so everyone can have at least a little bit of comfort in knowing for sure what happened to their family and friends. I feel for the families ....


Because it's a very large area and the equipment is costly. That part of the Indian Ocean is in a remote, uncharted territory. Storms that make it difficult to search as well.


These pings are jumping around, coming and going,
Three confirmed acoustic events now. Are these black boxes on the move? Is it possible a shark or other large sea mammal got caught up in some wreckage and is swimming around with it? Would a great white shark gobble it down ? 🐋
Silly idea, but there's so much mystery may as well toss it in with all the other hairbrained theories


edit on 6-4-2014 by violet because: (no reason given)



posted on Apr, 6 2014 @ 12:49 AM
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I believe they might have found it.

Reason one they got a pinger signal.

Two they got another pinger signal about a mile away.

There are two black boxes one is the flight data recorder.

The other is the cockpit recorder.

A aircraft hitting the water at high speed will break up one black box may sink slower then the other and drift a short distance away.



posted on Apr, 6 2014 @ 08:20 AM
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reply to post by ANNED
 


I just heard last night as I fell asleep. The Australians heard something also and I have great respect for our Aussie friends. They seem to have spearheaded this investigation and got lucky, now is where the fun begins.

Finding a ping in the ocean is about as hard as finding the orange box in the recovery area without a ping!
They better hurry up. . .



posted on Apr, 6 2014 @ 09:21 AM
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reply to post by AnteBellum
 


Well A.B., this looks like a legitimate lead
Nice find.



posted on Apr, 6 2014 @ 10:58 AM
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ANNED
A aircraft hitting the water at high speed will break up one black box may sink slower then the other and drift a short distance away.


Yes, an aircraft "hitting" the water at speed will "break up"...and leave debris all over the place!...Where is the debris?



posted on Apr, 6 2014 @ 11:14 AM
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Bedlam





Cool! Learn about him in school, did you? If so, then you missed half of what the man had to say about electromagnetic radiation.

But, I'll give that wee point to ya anyway, cause you are beginning to be correct...water does seriously attenuate EMF...(actually absorb...but that's okay for now)



You wouldn't use a ship's sonar to detect that sort of thing. A hydrophone system could, so any decent military ship would have gear that should be able to, our subs could do it easily. But you're not going to get them to do that, because it sort of gives away what and how well they can do. Not only that, since the signal isn't going to be very strong, you might do better with purpose-built designs.



No One wouldn't typically use a ships sonar to detect such things, but one can. You do know that sonar is little more than an underwater "speaker" and a "hydrophone array"? Right?

And, actually, no...it wouldn't give up any technological data about the equipment used...this application is far too basic to "give up" any information about the equipment used. Hell man...I could do the whole thing with my pc, a transducer and a microphone. Course, then again, I guess that is about as sophisticated as the US Navy, or any other military...lots of expensive toys, mostly outdated, and kept secret (probably so nobody will laugh at them).

But, seriously, that signal and its range are no better than the "radio set" contained in the system, and is only useful once the downed aircraft area has been determined. And that determination has either already been made with good accuracy, or it will NEVER be known (try on the ground in Pakistan, with possible involvement of the Pakistani government).


ETA: That 37.5 kHz acoustic signal would have done much better if it were RF. Would have been a better engineering decision, and made location easier as well.


edit on 6-4-2014 by tanka418 because: (no reason given)




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